Buffering salts are essential components in confections, playing a crucial role in maintaining the desired pH levels. They can be defined as substances that when in solution tend to stabilize the hydrogen ion concentration by neutralizing any added acid or alkali. These salts act as buffers by resisting changes in pH when acids or bases are added. This equilibrium between acid and base helps stabilize the pH, ensuring the confection's flavor, texture, and shelf life remain optimal.

The primary buffering salts used in confections are typically compounds like sodium citrate, potassium citrate, sodium acetate, sodium lactate and ammonium acetate, citrate and lactate. These salts are chosen for their specific buffering capacities and compatibility with various confectionery applications.

In confections Different combinations of acids and buffer salts can be used as buffers, for example, Malic Acid with Sodium Lactate

Buffer capacity refers to a buffer's ability to resist changes in pH. This capacity is influenced by the concentration of the buffer salt or acid solution, with higher concentrations leading to greater buffer capacity. It is commonly described in terms of the molarity of sodium hydroxide needed to increase the pH by 1.0 unit. The optimal buffering capacity occurs when the pH is near the pKa value of the acid in the buffer system. At this point, the buffer is most effective at maintaining a stable pH despite additions of acids or bases.

Different combinations of acids and buffer salts can be used as buffers, for example,

Malic Acid with Sodium Lactate or Citric acid and sodium citrate,

Now, here are the pKa values for each buffering salt mentioned:

Sodium Citrate: pKa1 = 3.13, pKa2 = 4.76, pKa3 = 6.40

Potassium Citrate: pKa1 = 3.13, pKa2 = 4.76, pKa3 = 6.40

Sodium Acetate: pKa = 4.76

Ammonium Acetate: pKa = 4.76

Sodium Lactate: pKa = 3.86

Ammonium Lactate: pKa = 3.86

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Buffers in confections have many uses that can be leverage all a time:

• Prevent the inversion of sucrose

• Prevent gelatin hydrolysis

• Control gelling of pectin

• Reduce flavor variation from two pH effects:

   • Changes in intensity of flavor chemicals with pH

    •Changes in sourness, sweet/sour balance

• Decrease variation in shade of natural pigments

• Reduce variation in texture from lot to lot.

• Extend shelf life

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If you are wondering how much to use which one is best for your confection, how you can combine the salts with the acids in your formul, one of our favorite suppliers, Corbion, have developed a fantastic tool to help you calculate the effect of adding different acids and salt buffers in the pH of your formula. You can check this incredible tool here!

Corbion Sourness & Stability Calculator

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A buffer must contain a weak acid and its conjugate base. There are several ways a solution containing these two components can be made:

- Buffers can be made from weak acids or base and their salts.

- Buffers can be made from two salts that provide a conjugate acid-base pair.

- Buffers can be made by adding a strong acid or base to a weak acid or base.

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• Hygroscopicity: Some buffering salts, like sodium lactate and ammonium lactate, exhibit hygroscopic properties, absorbing moisture and enhancing shelf life.

• Solubility: Most buffering salts are highly soluble in water, aiding in their incorporation into confections.

• pH: Each salt has a specific pH range where it is most effective as a buffer, influencing the confection's final pH.

• Shelf Stability: Properly buffered confections are less prone to pH-related spoilage, improving shelf stability.

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